Information processing apparatus and method, and recording medium

ABSTRACT

The present invention relates to an information processing apparatus and method, and a program in which information can be reliably exchanged when performing wireless communication by allowing a user to know a communication distance at which devices can be connected. A communication unit  28  performs Bluetooth communication with a communication unit, which serves as a Bluetooth module, provided for a cellular telephone. A CPU  21  displays an image corresponding to the cellular telephone based on the input level of Bluetooth radio waves transmitted from the cellular telephone. For example, when the input level of the radio waves transmitted from the cellular telephone is equal to the maximum input, the CPU  21  sets the level of transparency to be 0, and displays the image corresponding to the cellular telephone on an LCD  32  so that a background image is not transmitted at all. When the input level of the radio waves is almost equal to the reception sensitivity, the CPU  21  displays the image corresponding to the cellular telephone on the LCD  32  by setting the level of transparency to be 90% so as to transmit the background image. The present invention can be applied to an information processing apparatus, for example, a personal computer, a PDA, or a cellular telephone.

TECHNICAL FIELD

[0001] The present invention relates to information processingapparatuses and methods, and recording media, and more particularly, toan information processing apparatus and method, and a recording mediumin which communication can be performed via radio waves.

BACKGROUND ART

[0002] Cellular telephones and PDAs (Personal Digital Assistants) arecoming into widespread use. As a result of this, users exchangeinformation between a plurality of such devices more frequently.

[0003] Hitherto, when exchanging information as described above,information is sent and received by connecting devices with each othervia a cradle or a cable or by allowing infrared transmitters/receiversto face each other.

[0004] However, wired connection makes the operation troublesome andcomplicated, and also, a connector compatible with each device type mustbe prepared.

[0005] In infrared communication, if the user inadvertently passesthrough the infrared transmission channel, communication is interrupted.

[0006] It has been suggested that wireless communication is performedbetween a plurality of devices by using a wireless LAN (Local AreaNetwork) or a short-distance wireless LAN, for example, Bluetooth®.

[0007] However, when exchanging information, for example, between a PDAowned by the user and a device installed in front of the user, the useris unable to know whether communication can be made between the devicesunless he/she actually perform communication. In this manner, whenperforming wireless communication, the user is unable to know acommunication distance at which information can be exchanged byconnecting devices.

DISCLOSURE OF INVENTION

[0008] Accordingly, in view of this background, it is an object of thepresent invention to reliably exchange information when performingwireless communication by allowing a user to know a communicationdistance at which devices can be connected.

[0009] An information processing apparatus of the present inventionincludes: communication means for communicating with an electronicdevice via radio waves; and display control means for controlling animage corresponding to the electronic device to be displayed based onthe input level of the radio waves transmitted from the electronicdevice.

[0010] The information processing apparatus may further include:detection means for detecting that the electronic device is disposed inproximity with the information processing apparatus; and obtaining meansfor obtaining identification information concerning the electronicdevice when the detection means detects that the electronic device isdisposed in proximity with the information processing apparatus. Thecommunication means may communicate with the electronic device based onthe identification information.

[0011] The display control means may control the image to be displayedwith a level of transparency corresponding to the input level of theradio waves.

[0012] The display control means may control the image to be displayedat a position corresponding to the input level of the radio waves.

[0013] The display control means may control the image to be displayedwith a size corresponding to the input level of the radio waves.

[0014] The display control means may control the image to be displayedwith a level of resolution corresponding to the input level of the radiowaves.

[0015] The display control means may control the image to be displayedwith a level of saturation corresponding to the input level of the radiowaves.

[0016] The display control means may control the image to be displayedby performing mosaic processing on the image in accordance with theinput level of the radio waves.

[0017] An information processing method of the present inventionincludes: a communication processing step of communicating with anelectronic device via radio waves; and a display control processing stepof controlling an image corresponding to the electronic device to bedisplayed based on the input level of the radio waves transmitted fromthe electronic device.

[0018] A program recorded on a recording medium of the present inventionallows a computer to execute: a communication processing step ofcommunicating with an electronic device via radio waves; and a displaycontrol processing step of controlling an image corresponding to theelectronic device to be displayed based on the input level of the radiowaves transmitted from the electronic device.

[0019] According to the information processing apparatus and method, theprogram recorded on the recording medium of the present invention,communication is performed with an electronic device via radio waves,and the display of an image corresponding to the electronic device iscontrolled based on the input level of the radio waves transmitted fromthe electronic device.

BRIEF DESCRIPTION OF THE DRAWINGS

[0020]FIG. 1 illustrates an example of the configuration of aninformation processing system to which the present invention is applied.

[0021]FIG. 2 is a block diagram illustrating an example of theconfiguration of a personal computer shown in FIG. 1.

[0022]FIG. 3 is a block diagram illustrating the configuration of areader/writer 33.

[0023]FIG. 4 is a block diagram illustrating the configuration of acommunication unit 28.

[0024]FIG. 5 is a block diagram illustrating the configuration ofprograms executed by the personal computer 1.

[0025]FIG. 6 is a block diagram illustrating the configuration of acellular telephone 11.

[0026]FIG. 7 is a block diagram illustrating the configuration of an RFtag 212.

[0027]FIG. 8 illustrates an example of the functional blocks of thecellular telephone 11.

[0028]FIG. 9 is a flowchart illustrating the processing performed by thepersonal computer in the information processing system shown in FIG. 1.

[0029]FIG. 10 is a flowchart illustrating the processing performed bythe cellular telephone in the information processing system shown inFIG. 1.

[0030]FIG. 11 is a flowchart illustrating the processing performed bythe personal computer in the information processing system shown in FIG.1.

[0031]FIG. 12 is a flowchart illustrating the processing performed bythe cellular telephone in the information processing system shown inFIG. 1.

[0032]FIG. 13 illustrates the sending and receiving of data between thecellular telephone and the personal computer.

[0033]FIG. 14 is a flowchart illustrating the processing performed bythe cellular telephone in the example shown in FIG. 13.

[0034]FIG. 15 is a flowchart illustrating the processing performed bythe personal computer in the example shown in FIG. 13.

[0035]FIG. 16 illustrates an example of the display indicating thecommunication status.

[0036]FIG. 17 illustrates an example of the display indicating thecommunication status.

[0037]FIG. 18 illustrates an example of the display indicating thecommunication status.

[0038]FIG. 19 is a flowchart illustrating the processing for displayingthe radio wave status.

[0039]FIG. 20 illustrates an example of the display indicating thecommunication status.

[0040]FIG. 21 illustrates an example of the display indicating thecommunication status.

[0041]FIG. 22 illustrates an example of the display indicating thecommunication status.

[0042]FIG. 23 is a flowchart illustrating the processing for displayingthe radio wave status.

[0043]FIG. 24 illustrates an example of the configuration of acommunication system to which the present invention is applied.

[0044]FIG. 25 is a block diagram illustrating an example of theconfiguration of a PDA shown in FIG. 24.

[0045]FIG. 26 is a block diagram illustrating an example of a wirelessmodule shown in FIG. 25.

[0046]FIG. 27 is a flowchart illustrating the operation of thecommunication system shown in FIG. 24.

BEST MODE FOR CARRYING OUT THE INVENTION

[0047]FIG. 1 illustrates an example of the configuration of aninformation processing system to which the present invention is applied.In this example, a personal computer 1 is provided with an input displayunit 2 and a main unit 3 connected to the input display unit 2. Theinput display unit 2 displays predetermined information, and also,predetermined information can be input by operating, for example, a pen(not shown) on the input display unit 2.

[0048] If necessary, the user can place, for example, a cellulartelephone 11, on the input display unit 2 so as to send and receive databetween the cellular telephone 11 and the personal computer 1.

[0049]FIG. 2 illustrates an example of the configuration of the personalcomputer 1. A CPU (Central Processing Unit) 21 executes various types ofprocessing according to programs stored in a ROM (Read Only Memory) 22or a storage unit 26. A RAM (Random Access Memory) 23 suitably storesprograms, data, etc. executed by the CPU 21. The CPU 21, the ROM 22, andthe RAM 23 are connected to each other via a bus 24. An input/outputinterface 25 is also connected to the bus 24. The input/output interface25 is connected, not only to the input display unit 2, but also to thestorage unit 26 formed of, for example, a hard disk, and to acommunication unit 27 that communicates with other devices via, forexample, a telephone line.

[0050] A communication unit 28 is a so-called “Bluetooth module”. Thecommunication unit 28 performs Bluetooth communication with, forexample, a communication unit 213 (see FIG. 6), which is a Bluetoothmodule, provided for the cellular telephone 11.

[0051] Bluetooth is a wireless communication standard standardized bythe Bluetooth SIG (Special Interest Group), and a device communicateswith other devices provided with Bluetooth modules (hereinaftersometimes referred to as “Bluetooth devices”) by using the 2.4 GHz band(ISM (Industrial Science Medical) band).

[0052] A network formed by Bluetooth is referred to as “piconet” or“scatternet” formed of a plurality of piconets connected with each otherdepending on the network type, and in such a network, Bluetooth devices,which serve as a master and slaves, are provided. A Bluetooth device,which serves as a master, is simply referred to as a “master”, andBluetooth devices, which serve as slaves, are simply referred to as“slaves”.

[0053] After forming a piconet, in order to send and receive variousitems of information, it is necessary for all the Bluetooth devices inthe piconet to establish synchronization in the frequency domain and inthe time domain.

[0054] Establishing synchronization in the frequency domain and in thetime domain is briefly described.

[0055] In Bluetooth, for example, a master sends a signal to a slave byusing a frequency range of 79 MHz. In this case, instead of sendinginformation by using all the frequency range, the master sends theinformation by randomly changing (hopping) this frequency range in unitsof 1 MHz.

[0056] The slave, which is the receiving device, receives theinformation sent from the master by suitably changing the receptionfrequency in synchronization with the randomly changing transmissionfrequency of the master.

[0057] The frequency pattern changed by the master and the slave isreferred to as the “frequency hopping pattern”. When the frequencyhopping pattern is shared between the master and the slave, it meansthat the synchronization in the frequency domain is established.

[0058] In Bluetooth, since a master and a plurality of slaves performcommunication, the communication channel between the master and theslaves is divided in a time-division multiplexing manner in units of 625μs. The time intervals of the time units of 625 μs are referred to as“time slots”, and when the time slot is shared, it means that thesynchronization in the time domain is established.

[0059] All the slaves each calculate the frequency hopping pattern forestablishing synchronization in the frequency domain based on theBluetooth address of the master, and also adds an offset to theBluetooth clock managed by the slave based on the Bluetooth clock of themaster so as to provide timing for the time slot for establishingsynchronization in the time domain.

[0060] The Bluetooth address is represented by 48 bits unique to eachBluetooth device, and based on this address, the frequency hoppingpattern is uniquely calculated. The Bluetooth clock is managed by eachBluetooth device.

[0061] Accordingly, before forming a piconet, various items ofinformation including the Bluetooth addresses and the Bluetooth clocksfor establishing synchronization in the frequency domain and in the timedomain, respectively, are sent and received between the master and theslaves.

[0062] Referring back to FIG. 2, the input display unit 2 is providedwith a transparent tablet 31 for detecting the operation of a penperformed by the user, and an LCD (Liquid Crystal Display) 32 disposedunder the tablet 31 for displaying images of, for example, charactersand graphics. The input display unit 2 is also provided with areader/writer 33 that communicates with an RF tag 212 (FIG. 6) providedfor the cellular telephone 11.

[0063] A drive 29 is connected to the input/output interface 25, and amagnetic disk 41, an optical disc 42, a magneto-optical disk 43, or asemiconductor memory 44 is attached to this drive 29 when necessary. Aprogram read from the magnetic disk 41, the optical disc 42, themagneto-optical disk 43, or the semiconductor memory 44 is supplied fromthe drive 29 to the storage unit 26 via the input/output interface 25.

[0064]FIG. 3 is a block diagram illustrating an example of a detailedconfiguration of the reader/writer 33.

[0065] An IC 81 is formed of a CPU 91, an SPU (Signal Processing Unit)92, an SCC (Serial Communication Controller) 93, and a memory 94. Thememory 94 includes a ROM 101 and a RAM 102. The CPU 91, the SPU 92, theSCC 93, and the memory 94 are connected to each other via a bus 95.

[0066] The CPU 91 expands a control program stored in the ROM 101 to theRAM 102, and performs various types of processing based on response datasent from the RF tag 212 of the cellular telephone 11, which isdescribed below, or a control signal supplied from the CPU 21 shown inFIG. 2. For example, the CPU 91 generates a command to be sent to the RFtag 212 and outputs it to the SPU 92 via the bus 95, or authenticatesdata sent from the RF tag 212.

[0067] When the cellular telephone 11 is placed in proximity with thepersonal computer 1, and then, when the name of the Bluetooth device isreported according to the processing of the various elements, which isdescribed below, the CPU 91 informs the communication unit 28 that thecellular telephone 11 is placed close to the personal computer 1 basedon an instruction of the CPU 21.

[0068] When response data from the RF tag 212 is supplied from ademodulator 84, the SPU 92 performs, for example, BPSK (Binary PhaseShift Keying) demodulation, on that data, and supplies the resultingdata to the CPU 91. When a command to be sent to the RF tag 212 issupplied via the bus 95, the SPU 92 performs modulation (primarymodulation) on that command, and outputs the resulting data to amodulator 82.

[0069] The SCC 93 outputs data supplied from the CPU 21 to the CPU 91via the bus 95, and outputs data supplied from the CPU 91 via the bus 95to the CPU 21.

[0070] The modulator 82 performs ASK (Amplitude Shift Keying) modulationon the carrier wave of a predetermined frequency supplied from anoscillator circuit (OSC) 83 as the secondary modulation based on datasupplied from the SPU 92, and outputs the generated modulation wave froman antenna 85 as electromagnetic waves. Meanwhile, the demodulator 84demodulates a modulated wave (ASK-modulated wave) obtained via theantenna 85 and outputs the demodulated data to the SPU 92.

[0071] The antenna 85 radiates a predetermined electromagnetic wave, andthen, based on a change of the load with respect to the electromagneticwave, the antenna 85 detects whether the RF tag 212 (cellular telephone11) has been placed in proximity with the personal computer 1. When theRF tag 212 is placed in proximity with the personal computer 1, theantenna 85 sends and receives various items of data to and from the RFtag 212.

[0072]FIG. 4 is a block diagram illustrating an example of a detailedconfiguration of the communication unit 28, which serves as a Bluetoothmodule.

[0073] A CPU 121 expands a control program stored in a ROM 122 into aRAM 123, and controls the overall operation of the communication unit28. The CPU 121, the ROM 122, and the RAM 123 are connected to eachother via a bus 125, and a flash memory 124 is connected to the bus 125.

[0074] The flash memory 124 stores therein the name of a Bluetoothdevice that is set for each Bluetooth device and can be changedaccording to the user's favorite, and also stores the Bluetooth addressunique to each Bluetooth device.

[0075] The Bluetooth address is a 48-bit identifier, which is used forvarious types of processing for managing Bluetooth devices since it isinherent in (unique to) each Bluetooth device.

[0076] For example, as discussed above, for establishing synchronizationin a piconet, it is necessary for all the slaves to obtain informationconcerning the frequency hopping pattern of the master. This frequencyhopping pattern can be calculated by the slaves based on the Bluetoothaddress of the master.

[0077] More specifically, the Bluetooth address is formed of the lower24-bit LAP (Low Address Part), the next 8-bit UAP (Upper Address Part),and the remaining 16-bit NAP (Non-significant Address Part). Forcalculating the frequency hopping pattern, a total of 28 bits consistingof the whole 24 bits of LAP and the lower 4 bits of UAP are used.

[0078] Each slave is able to calculate the frequency hopping patternbased on the above-described 28 bits of the Bluetooth address of themaster, which is obtained when paging the master to establishsynchronization in the piconet, and based on the Bluetooth clockreported from the master.

[0079] In this frequency hopping pattern, the inquiry frequency hoppingpattern used when making an inquiry, the paging frequency hoppingpattern used when paging, and the channel frequency hopping pattern usedwhen performing communication between the master and a slave afterestablishing synchronization in the piconet are defined. The threefrequency hopping patterns are hereinafter simply referred to as the“frequency hopping pattern” unless they should be distinguished fromeach other.

[0080] The flash memory 124 stores link keys for authenticating aBluetooth device, which is a communicating party, or for encrypting datato be sent after establishing synchronization in a piconet, and providesthe stored link keys to the CPU 121 if necessary.

[0081] An input/output interface 126 manages input/output of datasupplied from the CPU 21 shown in FIG. 2 or data supplied from abaseband controller 127 based on an instruction from the CPU 121.

[0082] The baseband controller 127 outputs data supplied from theinput/output interface 126 to a GFSK (Gaussian Frequency Shift Keying)modulator 141 so as to send the data to the cellular telephone 11, andoutputs data supplied from a GFSK demodulator 147 to the bus 125 or theinput/output interface 126.

[0083] The GFSK modulator 141 restricts high frequency components ofdata supplied from the baseband controller 127 by using a filter so asto perform frequency modulation on the data as the primary modulation,and outputs the resulting data to a spread spectrum unit 142.

[0084] The spread spectrum unit 142 switches between the frequencycarriers based on the frequency hopping pattern calculated as describedabove and reported from a hopping synthesizer 145, performs spreadspectrum on the supplied data, and then outputs the resulting signal toa communication controller 143. In Bluetooth, the spread spectrum unit142 sends data by performing frequency hopping in every 625 μs.

[0085] The communication controller 143 sends the spread-spectrum signalfrom an antenna 144 by using the 2.4 GHz band. The communicationcontroller 143 also outputs a received signal from the antenna 144 to aninverse spread spectrum unit 146.

[0086] The inverse spread spectrum unit 146 hops the reception frequencybased on the frequency hopping pattern reported from the hoppingsynthesizer 145 so as to obtain, for example, a signal from the cellulartelephone 11. The inverse spread spectrum unit 146 also performs inversespread spectrum on a signal from the cellular telephone 11, and outputsthe reproduced signal to the GFSK demodulator 147. The GFSK demodulator147 performs GFSK demodulation on the signal supplied from the inversespread spectrum unit 146, and outputs the resulting data to the basebandcontroller 127.

[0087]FIG. 5 is a block diagram illustrating the configuration ofprograms executed by the personal computer 1. An operating system (basicprogram software) 161 is, for example, Windows® Me, Windows® 2000 byMicrosoft Corporation, or Mac OS® by Apple Computer Inc., and controlsthe basic operation of the computer.

[0088] A reader/writer control program 162 controls the reader/writer 33so as to detect the presence of a terminal integrating the RF tag 212therein which is placed in proximity with the personal computer 1 or tosend and receive various items of information to and from that terminalvia electromagnetic waves.

[0089] A Bluetooth control program 163 controls the communication unit28 so as to, for example, detect the presence of a Bluetooth deviceplaced in proximity with the personal computer 1 or to establishsynchronization for communicating with that Bluetooth device.

[0090] A display control program 164 controls the display of images of,for example, characters and graphics, on the LCD 32 of the input displayunit 2.

[0091] An e-mail program 165 sends e-mail to other devices, for example,a server, or receives e-mail from the other devices via thecommunication unit 27.

[0092]FIG. 6 illustrates an example of the configuration of the cellulartelephone 11. A CPU 201, a ROM 202, a RAM 203, a bus 204, and aninput/output interface 205 have functions basically similar to those ofthe CPU 21, the ROM 22, the RAM 23, the bus 24, and the input/outputinterface 25, respectively, of the personal computer 1 shown in FIG. 2,and an explanation thereof is thus omitted.

[0093] In the cellular telephone 11, the input/output interface 205 isconnected to an input unit 206 formed of, for example, various buttonsand switches, and is also connected to an LCD 207 for displayingpredetermined information. A storage unit 208 formed of, for example, asemiconductor memory, and a communication unit 209 for performingcommunication via a telephone line are also connected to theinput/output interface 205.

[0094] A microphone 210 records user voice therein, and a speaker 211outputs sound to the user. The RF tag 212 has a built-in IC, andcommunicates with the reader/writer 33 of the personal computer 1 so asto send the name of the Bluetooth device integrated in the cellulartelephone 11 to the reader/writer 33. The RF tag 212 has the function ofstoring data supplied from the reader/writer 33 in a built-in memory.

[0095] A communication unit 213 is a Bluetooth module. The communicationunit 213 forms, for example, a piconet with the communication unit 28 ofthe personal computer 1, and sends and receives various items of databased on an instruction from the CPU 201.

[0096] The configuration of the communication unit 213 is similar tothat of the communication unit 28 shown in FIG. 4, and a detailedexplanation thereof is thus omitted.

[0097]FIG. 7 is a block diagram illustrating an example of a detailedconfiguration of the RF tag 212.

[0098] The RF tag 212 is formed of, for example, a one-chip IC in whichan antenna 240 shown in FIG. 7 and the elements other than the antenna240 are stored. An example of the devices having a function basicallysimilar to that of the RF tag 212 is Felica®.

[0099] A CPU 231 expands a control program stored in a ROM 232 into aRAM 233 so as to control the overall operation of the RF tag 212. Whenelectromagnetic waves radiating from the reader/writer 33 are receivedby the antenna 240, the CPU 231 reports ID information set in the RF tag212 to the reader/writer 33 accordingly.

[0100] The setting of the ID information can be changed as desired, andthe ID information contains, for example, the same name as the name ofthe Bluetooth device set in the communication unit 213 (cellulartelephone 11), which serves as a Bluetooth module, or a name containingthat Bluetooth device name.

[0101] In FIG. 7, a data sender 237, a BPSK modulator 238, a BPSKdemodulator 241, and a data receiver 242 correspond to the SPU 92 of thereader/writer 33 shown in FIG. 3, and an ASK modulator 252 and an ASKdemodulator 253 correspond to the modulator 82 and the demodulator 84,respectively. The basic processing is similar to that described above,and a detailed explanation is thus omitted.

[0102] For example, when the cellular telephone 11 is placed inproximity with the personal computer 1, ID information is read from anEEPROM 234 and is output to the data sender 237. The ID informationsupplied to the data sender 237 is subjected to BPSK modulation in theBPSK modulator 238 as the primary modulation, and is then output to theASK modulator 252.

[0103] The ASK modulator 252, for example, turns ON/OFF a predeterminedswitching device in accordance with the data supplied from the BPSKmodulator 238 so as to change the load of the antenna 240. The ASKmodulator 252 then performs ASK modulation on a modulation wave from thereader/writer 33 received by the antenna 240 so as to send the modulatedcomponents to the reader/writer 33 (changes the terminal voltage of theantenna 85 of the reader/writer 33).

[0104] In addition to the reporting of the ID information to thepersonal computer 1, the RF tag 212 performs various types ofprocessing, for example, authentication processing with thereader/writer 33 and encryption processing of data to be sent.

[0105]FIG. 8 illustrates an example of functional blocks of the cellulartelephone 11.

[0106] A host program 271 provides basic functions of the cellulartelephone 11, for example, a calling function and an e-mailsending/receiving function. An RF-tag control program 272 controls theoperation of the RF tag 212, and also performs various types ofprocessing based on an instruction from the host program 271.

[0107] For example, when the cellular telephone 11 is placed inproximity with the personal computer 1, the RF-tag control program 272provides set ID information to the reader/writer 33, and starts thecommunication unit 213 (Bluetooth control program 273), which serves asa Bluetooth module, upon receiving electromagnetic waves from thereader/writer 33.

[0108] The Bluetooth control program 273 controls the operation of thecommunication unit 213 so as to implement communication with otherBluetooth devices.

[0109] The operations performed by the personal computer 1 and thecellular telephone 11 are described below with reference to theflowcharts of FIGS. 9 and 10. When the user wishes to send and receivedata between the cellular telephone 11 and the personal computer 1,he/she places the cellular telephone 11 at a predetermined position (ata position, indicated by the broken lines in FIG. 1, in which thereader/writer 33 is disposed) of the input display unit 2.

[0110] The reader/writer 33 regularly sends electromagnetic waves atsufficiently short intervals, and when the cellular telephone 11 isplaced on the input display unit 2 (on the reader/writer 33), theequivalent impedance of the antenna integrated in the reader/writer 33changes due to the electromagnetic coupling between the reader/writer 33and the RF tag 212 of the cellular telephone 11. In step S1 of FIG. 9,under the control of the reader/writer control program 162, thereader/writer 33 monitors this impedance change so as to determinewhether the cellular telephone 11 is placed on the reader/writer 33, andwaits until the cellular telephone 11 is placed.

[0111] When the cellular telephone 11 is placed on the reader/writer 33,in step S2, the reader/writer 33 requests the cellular telephone 11 tosend the name of the Bluetooth device corresponding to the communicationunit 213 under the control of the reader/writer control program 162.

[0112] In response to this request, the name of the Bluetooth device issent from the cellular telephone 11, as described below. Then, in stepS3, the reader/writer 33 waits until it receives the name of theBluetooth device from the cellular telephone 11 under the control of thereader/writer control program 162, and upon receiving this, the processproceeds to step S4. In step S4, the reader/writer 33 supplies thereceived name of the Bluetooth device of the cellular telephone 11 tothe CPU 21. The CPU 21 then supplies the name of the Bluetooth device tothe RAM 23 and stores it therein under the control of the reader/writercontrol program 162.

[0113] Then, in step S5, the CPU 21, which executes the Bluetoothcontrol program 163, controls the communication unit 28 to connect tothe Bluetooth device corresponding to the device name of the cellulartelephone 11 stored in step S4, thereby setting a link required fortransferring data.

[0114] More specifically, when the communication unit 213 of thecellular telephone 11 is in the waiting phase, the CPU 21 controls thecommunication unit 28 to inquire and page a synchronization establishingphase so as to establish synchronization with the communication unit213.

[0115] Upon establishing synchronization between the communication unit28 and the communication unit 213, the communication unit 28 of thepersonal computer 1 and the communication unit 213 of the cellulartelephone 11 shift to the communication connection phase.

[0116] The CPU 21 controls the communication unit 28 to send a controlpacket for setting a communication link to the Bluetooth devicecorresponding to the device name of the cellular telephone 11, i.e., thecommunication unit 213, among the Bluetooth devices in the piconet inwhich the synchronization in the frequency domain and in the time domainis established, thereby establishing an ACL (AsynchronousConnection-Less) link required for the processing of the subsequentstep.

[0117] Thereafter, in step S6, the personal computer 1 performspredetermined processing with the cellular telephone 11 via a network.Specific examples of the processing are described below.

[0118] Meanwhile, in step S11 of FIG. 10, the RF tag 212 of the cellulartelephone 11 determines whether electromagnetic waves from thereader/writer 33 of the personal computer 1 have been received (whetherthe cellular telephone 11 is placed on the input display unit 2 of thepersonal computer 1). If it is determined that the cellular telephone 11is placed on the input display unit 2, the process proceeds to step S12.In step S12, the RF tag 212 waits for a request to send the name of theBluetooth device under the control of the RF-tag control program 272. Asdiscussed above, the reader/writer 33 of the personal computer 1requests the cellular telephone 11 to send the name of the Bluetoothdevice in step S2. If it is determined that this request has beenreceived, the process proceeds to step S13 in which the RF tag 212 readsthe name of the Bluetooth device stored in the built-in memory and sendsit to the reader/writer 33 under the control of the RF-tag controlprogram 272.

[0119] The name of the Bluetooth device may be stored in the ROM 202 orthe storage unit 208, in which case, the name read from the ROM 202 orthe storage unit 208 by the CPU 201 is sent from the RF tag 212.

[0120] In step S14, the CPU 201 of the cellular telephone 11, whichexecutes the Bluetooth control program 273, waits until thecommunication unit 28 of the personal computer 1 and the communicationunit 213 are connected to each other via Bluetooth communication (inthis case, until the communication units 28 and 213 shift to thecommunication connection phase).

[0121] If the communication unit 213 determines in step S14 that it isconnected to the communication unit 28 of the personal computer 1 viaBluetooth communication under the control of the Bluetooth controlprogram 273, the process proceeds to step S15. Since the communicationunit 28 of the personal computer 1 sends a control packet for settingthe communication link in step S5, the communication unit 213 receivesthis control packet so as to set the communication link with thepersonal computer 1.

[0122] Thereafter, the process proceeds to step S16 in which thecellular telephone 11 performs predetermined processing with thepersonal computer 1 via a network. This processing corresponds to theprocessing of step S6 of FIG. 9.

[0123] In the above-described example, the name of the Bluetooth deviceof the cellular telephone 11 is sent and received as the ID information.An ID number other than the name of the Bluetooth device of the cellulartelephone 11 may be sent from the cellular telephone 11 to the personalcomputer 1, and the personal computer 1 may search for the name of theBluetooth device of the cellular telephone 11 as the network addressbased on the ID number.

[0124]FIGS. 11 and 12 illustrate the operations of the personal computer1 and the cellular telephone 11, respectively, in this modification.

[0125] Operations of steps S51 through S56 of the cellular telephone 11shown in FIG. 12 are basically similar to those of steps S11 through S16of FIG. 10. The process shown in FIG. 12 is different from that of FIG.10 in that, in step S52, instead of the device name, the ID number isrequested from the personal computer 1, and the data sent in step S53 isnot the device name, but the ID number. Operations other than steps S52and S53 are similar to those of FIG. 10.

[0126] Similarly, operations in steps S31 through S37 of the personalcomputer 1 shown in FIG. 11 are basically similar to those in steps S1through S6 of FIG. 9. In the process of FIG. 11, however, instead of thename of the Bluetooth device being directly sent from the cellulartelephone 11, the ID number is sent. Accordingly, in step S34, the CPU21 of the personal computer 1 stores the ID number of the cellulartelephone 11 in the RAM 23, and then, in step S35, the CPU 21 searchesfor the name of the Bluetooth device from the ID number of the cellulartelephone 11. For searching for the device name, a table in which the IDnumber of the cellular telephone 11 is associated with the name of theBluetooth device may be prestored in the storage unit 26. Alternatively,the communication unit 27 may access a predetermined server via, forexample, the Internet, so as to search for the name of the Bluetoothdevice corresponding to the ID number of the cellular telephone 11 viathis server.

[0127] The process after searching for the name of the Bluetooth deviceof the cellular telephone 11 is similar to that of FIG. 9.

[0128] A further explanation of examples of the operation executed instep S6 of FIG. 9 (step S37 of FIG. 11) and the operation executed instep S16 of FIG. 10 (step S56 of FIG. 12) is given below.

[0129]FIG. 13 illustrates an example in which a mail message registeredin the cellular telephone 11 is enlarged and displayed on the LCD 32 ofthe input display unit 2 by placing the cellular telephone 11 on theinput display unit 2.

[0130] The processing performed by the cellular telephone 11 and theprocessing performed by the personal computer 1 in this case aredescribed below with reference to the flowcharts of FIGS. 14 and 15.

[0131] In step S71 of FIG. 14, the CPU 201 of the cellular telephone 11reads the senders and the subjects of mail messages received so far andstored in the RAM 203. Then, in step S72, the CPU 201 allows thecommunication unit 213 to send the read senders and subjects of the mailmessages to the personal computer 1. That is, in this case, the CPU 201controls the communication unit 213 to send the senders and subjects ofthe mail messages to the personal computer 1 via Bluetoothcommunication.

[0132] The senders and subjects of the mail messages are displayed onthe LCD 32 of the personal computer 1, as described below, and when theuser selects a predetermined sender and subject, information concerningthat selection is sent to the cellular telephone 11.

[0133] Then, in step S73, the CPU 201 waits until it is reported thatthe mail has been selected, and when it is reported that the mail hasbeen selected, the process proceeds to step S74. In step S74, the mailmessage is read from the RAM 203 and is sent from the communication unit213 to the personal computer 1.

[0134] In accordance with the process of the cellular telephone 11, thepersonal computer 1 executes the process indicated by the flowchart ofFIG. 15.

[0135] First, in step S81, the CPU 21 receives the mail senders andsubjects from the cellular telephone 11. More specifically, thecommunication unit 28 receives the mail senders and subjects from thecommunication unit 213 of the cellular telephone 11 via Bluetoothcommunication, and supplies them to the RAM 23 and stores them therein.

[0136] In step S82, the CPU 21 reads the senders and subjects stored inthe RAM 23, and outputs them to the LCD 32 and displays them.Accordingly, the mail senders and subjects sent from the cellulartelephone 11 are displayed in a window 301, such as that shown in FIG.13.

[0137] The user operates the pen by viewing this display and specifiesthe sender or the subject of one of the mail messages within the window301 so as to select the mail. Then, in step S83, the CPU 21 waits untilthe mail is selected, and when the mail is selected, the processproceeds to step S84. In step S84, the CPU 21 informs the cellulartelephone 11 of the selected mail. That is, in this case, the CPU 21controls the communication unit 28 to inform the cellular telephone 11which mail has been specified (selected) by the user via Bluetoothcommunication.

[0138] After informing the cellular telephone 11 of the selected mail,as stated above, the selected mail message is sent from the cellulartelephone 11. Then, in step S85, the communication unit 28 receives themail message sent from the cellular telephone 11. The mail message istemporarily supplied to the RAM 23 and is stored therein. Then, in stepS86, the CPU 21 reads the mail message stored in the RAM 23, and outputsit to the right side of the position at which the cellular telephone 11is placed on the LCD 32 or to a position specified by the user with thepen (such a position is detected from an output of the tablet 31) anddisplays the message. Accordingly, the selected mail message isdisplayed in the window 302, such as that shown in FIG. 13. In theexample of FIG. 13, the message of the second mail (the sender is BBBand the subject is bb) in the window 301 is displayed as “Hello. It's anice weather, isn't it?”.

[0139] Theoretically, it is possible to send and receive mail data bycommunication between the RF tag 212 and the reader/writer 33. However,since the transmission capacity of this type of communication is small,the communication is limited to the sending of ID information in thepresent invention.

[0140] A display indicating the communication status in the informationprocessing system of the present invention is described below.

[0141]FIGS. 16 through 18 illustrate a first example of the displayindicating the communication status in the information processing systemof the present invention. When the cellular telephone 11 is positionedin the proximity with the personal computer 1, as shown in FIG. 16, andwhen the electric field formed by the cellular telephone 11 issufficiently strong at the position at which the personal computer 1 isdisposed, the input level of the radio waves transmitted from thecellular telephone 11 and received by the communication unit 28 issufficiently high.

[0142] When the input level of the radio waves transmitted from thecellular telephone 11 is equal to the maximum input, the personalcomputer 1 sets the level of transparency to be 0, and displays an image321 corresponding to the cellular telephone 11 on the LCD 32 of theinput display unit 2 so that the background image is not transmitted atall.

[0143] When the cellular telephone 11 is positioned in a mid-point ofthe communication range of the personal computer 1 (for example, thedistance between the personal computer 1 and the cellular telephone 11is about 5 m), as shown in FIG. 17, and when the input level of theradio waves transmitted from the cellular telephone 11 and received bythe communication unit 28 is about one half the maximum input, thepersonal computer 1 sets the level of transparency to be, for example,50%, and displays the image 321 corresponding to the cellular telephone11 on the LCD 32 of the input display unit 2.

[0144] That is, the personal computer 1 adds, for example, ½ of thepredetermined pixel values of the original image 321 to ½ of the pixelvalues of the background image, thereby calculating the values of atranslucent image. The personal computer 1 then displays the translucentimage 321 corresponding to the cellular telephone 11 on the LCD 32 ofthe input display unit 2 based on the calculated pixel values.

[0145] When the cellular telephone 11 is positioned at the end of thecommunication range of the personal computer 1 (for example, thedistance between the personal computer 1 and the cellular telephone 11is about 10 m), as shown in FIG. 18, and when the input level of theradio waves transmitted from the cellular telephone 11 and received bythe communication unit 28 is about the same as the receptionsensitivity, the personal computer 1 sets the level of transparency tobe, for example, 90%, and displays the image 321 corresponding to thecellular telephone 11 on the LCD 32 of the input display unit 2.

[0146] That is, the personal computer 1 adds, for example, 10% of thepixel values of the original image 321 to 90% of the pixel values of thebackground image, thereby calculating the pixel values corresponding tothe image 321. The personal computer 1 then displays the almosttransparent image 321 corresponding to the cellular telephone 11 on theLCD 32 of the input display unit 2 based on the calculated pixel values.

[0147]FIG. 19 is a flowchart illustrating a process of displaying theradio wave status by the personal computer 1.

[0148] In step S101, the CPU 121 of the communication unit 28 of thepersonal computer 1 obtains the input level of the radio waves receivedfrom the cellular telephone 11 from an RF unit 128 via the bus 125. TheCPU 121 supplies data indicating the input level to the CPU 21 via theinput/output interface 126 and the input/output interface 25.

[0149] In step S102, the CPU 21 of the personal computer 1, whichexecutes the display control program 164, calculates the level oftransparency corresponding to the input level based on the dataindicating the radio waves. The CPU 21 calculates the level oftransparency by, for example, dividing the obtained data indicating theinput level by a predetermined constant.

[0150] The CPU 21 may determine the level of transparency by comparingthe data indicating the input level with at least one prestoredthreshold. Alternatively, the CPU 21 may determine the level oftransparency based on a table, which is prestored in the storage unit26, in which the input levels and the levels of transparency areassociated with each other.

[0151] In step S103, the CPU 21, which executes the display controlprogram 164, designates the level of transparency calculated in theprocessing of step S102 so as to display the image of the device of thecommunicating party on the LCD 32 of the input display unit 2. Theprocess then returns to step S101, and the display processing isrepeated. If the communicating party is, for example, the cellulartelephone 11, the CPU 21 designates the level of transparency calculatedin the processing of step S102 so as to display the image 321corresponding to the cellular telephone 11 on the LCD 32 of the inputdisplay unit 2.

[0152] As described above, the personal computer 1 is able to displaythe image of a communicating party on the input display unit 2 byvarying the level of transparency in accordance with the radio wavestatus. Thus, the user is able to quickly understand the radio wavestatus, namely, the communication status.

[0153] The user can determine the position of the cellular telephone 11so that the image having the lowest level of transparency is displayedon the input display unit 2, thereby making it possible to exchangeinformation more reliably between the personal computer 1 and thecellular telephone 11.

[0154]FIGS. 20 through 22 illustrate a second example of the displayindicating the communication status in the information processing systemof the present invention. When the cellular telephone 11 is placed inproximity with the personal computer 1, as shown in FIG. 20, and whenthe input level of the radio waves transmitted from the cellulartelephone 11 is equivalent to the maximum input, the personal computer 1displays an image 341 corresponding to the cellular telephone 11 at thecenter of the LCD 32 of the input display unit 2.

[0155] When the cellular telephone 11 is positioned at a mid-point ofthe communication range of the personal computer 1, as shown in FIG. 21,and when the input level of the radio waves transmitted from thecellular telephone 11 and received by the communication unit 28 is aboutone half the maximum input, the personal computer 1 displays the image341 corresponding to the cellular telephone 11, for example, on adiagonal line of the display surface of the LCD 32 at which the distancefrom the image 341 to the center of the LCD 32 and the distance from theimage 341 to the corner of the LCD 32 are the same.

[0156] When the cellular telephone 11 is positioned at the end of thecommunication range of the personal computer 1, as shown in FIG. 22, andwhen the input level of the radio waves transmitted from the cellulartelephone 11 and received by the communication unit 28 is almost equalto the reception sensitivity, the personal computer 1 displays the image341 corresponding to the cellular telephone 11 at the corner of the LCD32 of the input display unit 2.

[0157]FIG. 23 is a flowchart illustrating another process of displayingthe radio wave status by the personal computer 1.

[0158] In step S121, the CPU 121 of the communication unit 28 of thepersonal computer 1 obtains the input level of the radio waves receivedfrom the cellular telephone 11 from the RF unit 128 via the bus 125. TheCPU 121 then supplies data indicating the input level to the CPU 21 viathe input/output interface 126 and the input/output interface 25.

[0159] In step S122, the CPU 21 of the personal computer 1, whichexecutes the display control program 164, calculates the displayposition based on the data indicating the input level of the radiowaves. For example, when the input level of the radio waves is higher,the CPU 21 calculates coordinates closer to the center of the LCD 32 ona diagonal line of the display surface of the LCD 32. When the inputlevel of the radio waves is lower, the CPU 21 calculates coordinatescloser to the corner of the LCD 32 on a diagonal line of the displaysurface of the LCD 32.

[0160] In step S123, the CPU 21, which executes the display controlprogram 164, designates the display position corresponding to the inputlevel calculated in the processing of step S122 so as to display theimage of the device of the communicating party. The process then returnsto step S121, and the display processing is repeated. If thecommunicating party is, for example, the cellular telephone 11, the CPU21 designates the display position calculated in the processing of stepS122 so as to display the image 341 corresponding to the cellulartelephone 11 on the LCD 32 of the input display unit 2.

[0161] As described above, the personal computer 1 is able to displaythe image of a communicating party on the input display unit 2 byvarying the position in accordance with the radio wave status. Then, theuser is able to quickly understand the radio wave status, namely, thecommunication status.

[0162] The user can determine the position of the cellular telephone 11so that the image is displayed at a position closer to the center of theinput display unit 2, thereby making it possible to exchange informationmore reliably between, the personal computer 1 and the cellulartelephone 11.

[0163] The personal computer 1 may display the image of a communicatingparty on the input display unit 2 by changing the size of the image inaccordance with the radio wave status. For example, when the input levelof the radio waves transmitted from the cellular telephone 11 is higher,the personal computer 1 may display a larger image of the communicatingparty on the input display unit 2. When the input level of the radiowaves transmitted from the cellular telephone 11 is lower, the personalcomputer 1 may display a smaller image of the communicating party on theinput display unit 2.

[0164] Alternatively, the personal computer 1 may perform mosaicprocessing corresponding to the radio wave status on the image of acommunicating party so as to display the image subjected to mosaicprocessing on the input display unit 2. For example, when the inputlevel of the radio waves transmitted from the cellular telephone 11 issufficiently high, the personal computer 1 displays a sharp image of thecommunicating party on the input display unit 2. When the input level ofradio waves transmitted from the cellular telephone 11 is low, thepersonal computer 1 displays a mosaic-processed image of thecommunicating party on the input display unit 2. The personal computer 1varies the level of mosaic processing performed on the image of thecommunicating party in accordance with the input level of the radiowaves transmitted from the cellular telephone 11.

[0165] Alternatively, the personal computer 1 may display the image of acommunicating party on the input display unit 2 by changing the color ofthe image in accordance with the radio wave status. For example, whenthe input level of the radio waves transmitted from the cellulartelephone 11 is higher, the personal computer 1 displays a highersaturation image (a so-called sharp image) of the communicating party onthe input display unit 2. When the input level of the radio wavestransmitted from the cellular telephone 11 is lower, the personalcomputer 1 displays a lower saturation image (a so-called faint image)of the communicating party on the input display unit 2. The personalcomputer 1 may display the image of a communicating party on the inputdisplay unit 2 by changing the color density, the color hue, or theluminance of the image in accordance with the radio wave status.

[0166] Alternatively, the personal computer 1 may display the image of acommunicating party on the input display unit 2 by changing the spatialresolution of the image in accordance with the radio wave status. Forexample, when the input level of the radio waves transmitted from thecellular telephone 11 is higher, the personal computer 1 may display animage containing more high-frequency components of the communicatingparty on the input display unit 2. When the input level of the radiowaves transmitted from the cellular telephone 11 is lower, the personalcomputer 1 may display an image containing less high-frequencycomponents (a so-called blurred image) of the communicating party on theinput display unit 2.

[0167] The personal computer 1 may display on the input display unit 2an image obtained by changing the level of transparency, the size, thesaturation, etc. in a mixed manner in accordance with the radio wavestatus.

[0168] It has been described that the personal computer 1 displays theimage corresponding to the input level of the radio waves received bythe communication unit 28 on the input display unit 2. However, thepersonal computer 1 may display the image corresponding to the intensityof electromagnetic coupling between the reader/writer 33 and the RF tag212 on the input display unit 2.

[0169] The ID number is sent and received between the RF tag and thereader/writer. Alternatively, a barcode may be printed on eachelectronic device, and the ID number can be sent and received by readingthe barcode.

[0170] Although Bluetooth is used as a network by way of example, atelephone line, a LAN, a wireless LAN, a WAN, the Internet, etc., may beused.

[0171] As the information processing apparatus on which an electronicdevice is placed, not only an input display unit, but also a palm rest,a mouse pad, or a white board of a notebook personal computer may beused.

[0172] It has been described that the telephone number is used as the IDnumber by way of example. However, any number may be used as long as itis required for accessing the electronic device in the network.

[0173] Authentication for a communicating party may be performed whensending and receiving the ID number.

[0174] The terminal of a communicating party performing Bluetoothcommunication is specified based on the ID or the name of the Bluetoothdevice stored in the RF tag 212 of the cellular telephone 11. However,even if the RF tag 212 is not provided for the cellular telephone 11,the terminal of the communicating party can be specified by controllingthe output power of the radio waves of the communication unit 213, whichserves as a wireless module (Bluetooth module).

[0175] A description is now given of a communication system in which theterminal of a communicating party can be specified by controlling theoutput power of radio waves output from a wireless module.

[0176]FIG. 24 is a diagram illustrating an example of the configurationof the communication system in which the terminal of a communicatingparty can be specified by controlling the output power of radio waves.

[0177] In this example, although a description is given of communicationbetween the personal computer 1 and a PDA 501, the same operation can beperformed when the cellular telephone 11 is used instead of the PDA 501.

[0178] For example, when a communicating party performing Bluetoothcommunication is specified to establish communication with thatcommunicating party, the PDA 501 first restricts the output power of acommunication module 511 to a minimal level so that radio waves reachonly within a range of a few centimeters. In the extremely small powermode in which the output power of radio waves is restricted as describedabove, the communication module 511 repeatedly performs “inquiry” tosearch for devices positioned in a range that can be reached by theradio waves (for example, within a range of a few centimeters).

[0179] When the user places or positions the PDA 501 on or in proximitywith the personal computer 1 so that the radio waves radiated from thecommunication module 511 are received by the communication unit 28(wireless module) of the personal computer 1, the communication unit 28responds to the inquiry. Thus, the communication module 511 performsinquiry and paging with the communication unit 28, as stated above, soas to establish a communication link. This communication link iseffective only within a very narrow area that can be reached by radiowaves from the communication module 511 in which the extremely low powermode is set.

[0180] Accordingly, the communication module 511 temporarily disconnectsthe communication link so as to switch the power mode of thecommunication module 511 from the extremely low power mode to the normalpower mode so that communication can be performed with the communicationunit 28 even if the PDA 501 is away from the personal computer 1 at acertain distance. Then, the communication module 511 reestablishes thecommunication link with the communication unit 28 based on theinformation obtained (the information obtained by inquiry and paging inshort-distance communication).

[0181] The reestablished communication link becomes effective within arange of a few dozen of meters that can be reached by radio waves in amanner similar to normal Bluetooth communication, and Bluetoothcommunication can be performed even when the distance between thepersonal computer 1 and the PDA 501 is sufficiently wide.

[0182] As described above, even when an RF tag in which the ID or thename of a Bluetooth device is stored is not provided for the PDA 501,the output power of the communication module is controlled, and then,the user merely places the PDA 501 in proximity with the personalcomputer 1 to establish Bluetooth communication.

[0183] If the power mode of the communication module 511 can beseamlessly switched, it may be switched from the extremely low powermode to the normal power mode without temporarily disconnecting thecommunication link established when the extremely low power mode is set.

[0184]FIG. 25 is a block diagram illustrating an example of theconfiguration of the PDA 501 shown in FIG. 24.

[0185] The configuration of the PDA 501 is basically similar to that ofthe cellular telephone 11 shown in FIG. 6, except that the communicationunit 209 (a communication module that performs communication via atelephone line), the microphone 210, the speaker 211, and the RF tag 212are not provided, and an explanation thereof is thus omitted.

[0186] A CPU 521 controls the overall operation of the PDA 501 accordingto, for example, a program expanded from a ROM 522 into a RAM 523, andcontrols the output power of radio waves transmitted from thecommunication module 511 according to the communication status, asdescribed above.

[0187]FIG. 26 is a block diagram illustrating an example of a detailedconfiguration of the communication module 511 shown in FIG. 25.

[0188] The communication module 511 can be a Bluetooth module or awireless LAN module, and if it serves as a Bluetooth module, theconfiguration thereof encompasses the configuration of the communicationunit 28 shown in FIG. 4. The configuration of the communication module(Bluetooth module) 511 in FIG. 26 is shown in a simplified form comparedto that shown in FIG. 4 so as to avoid the repetition of the sameexplanation.

[0189] A wireless controller 541 controls a changeover switch 544. Whensending information to an external terminal from the communicationmodule 511, the wireless controller 541 connects a switch 544A to acontact a. When receiving information from an external terminal, thewireless controller 541 connects the switch 544A to a contact b. Basedon the control performed by the CPU 521 via the bus 524 and theinput/output interface 525, the wireless controller 541 controls thegain of a power amplifier 545 so as to regulate the range (output power)that can be reached by radio waves radiated from an antenna 547.

[0190] More specifically, when an instruction is given from the CPU 521to set the extremely low power mode, the wireless controller 541controls the gain of the power amplifier 545 so that the range that canbe reached by radio waves radiated from the antenna 547 is restricted toa minimal level. In contrast, when an instruction is given from the CPU521 to switch from the extremely low power mode to the normal power modeafter specifying the terminal of a communicating party, the wirelesscontroller 541 controls the gain of the power amplifier 545 so that therange that can be reached by radio waves becomes wider.

[0191] As in the baseband controller 127 shown in FIG. 4, a basebandcontroller 542 controls the baseband signal of transmission/receptionsignals. A modulation/demodulation processor 543 performs GFSKmodulation and spread spectrum based on the hopping frequency on theoutput from the baseband controller 542, and outputs the resultingsignal from the antenna 547 via the power amplifier 545. Themodulation/demodulation processor 543 also performs inverse spreadspectrum and GFSK demodulation on the output from an LNA (Low NoiseAmplifier), and outputs the resulting signal to the baseband controller542.

[0192] The configuration of the personal computer 1 is similar to theconfiguration shown in FIG. 2, and an explanation thereof is thusomitted. In the communication system shown in FIG. 24, it is notnecessary that the reader/writer 33 shown in FIG. 2 be provided for thepersonal computer 1.

[0193] The operation of the communication system shown in FIG. 24 isdescribed below with reference to the flowchart of FIG. 27. In thisexample, it is assumed that a communicating party performing Bluetoothcommunication is specified to establish communication.

[0194] For example, when an instruction is given from the user toperform Bluetooth communication, the communication module 511 is startedunder the control of the CPU 521. In step S201, the extremely low powermode is set as the power mode of the communication module 511. Thecommunication module 511 then proceeds to step S202 in which itrepeatedly performs inquiry to search for a terminal placed in proximitywith the PDA 501. Since the extremely low power mode is set to limit therange that can be reached by radio waves to a minimal level, during theinquiry performed in step S202, an IQ packet (inquiry packet) isrepeatedly broadcast in a range of a few centimeters from the antenna547.

[0195] Meanwhile, in step S211, the communication unit 28 of thepersonal computer 1 repeatedly performs inquiry scanning and pagingscanning, and waits for an inquiry or paging request from anotherterminal.

[0196] When the user places the PDA 501 in proximity with the personalcomputer 1, and when the communication unit 28 of the personal computer1 is within the range that can be reached by radio waves from thecommunication module 511 of the PDA 501, an IQ packet broadcast from thecommunication module 511 is received by the communication unit 28 instep S222.

[0197] Upon receiving the IQ packet broadcast from the communicationmodule 511, the communication unit 28 proceeds to step S223 to respondto the IQ packet. In step S223, the communication unit 28 sends an FHSpacket to the communication module 511. This FHS packet containsinformation indicating the Bluetooth address and the Bluetooth clock ofthe personal computer 1 as attribute information of the personalcomputer 1 (Bluetooth slave).

[0198] Upon receiving the FHS packet sent from the communication unit 28in step S203, the communication module 511 proceeds to step S204 inwhich the communication module 511 requests the communication unit 28 toconnect to the communication module 511.

[0199] More specifically, when the ID packet is sent from thecommunication module 511 to the communication unit 28, and when the sameID packet as the ID packet sent from the communication module 511 isreturned from the communication unit 28 to the communication module 511,an FHS packet containing the Bluetooth address and the Bluetooth clockof the communication module 511 is sent from the communication module511 to the communication unit 28.

[0200] When receiving the FHS packet sent from the communication module511 by the communication unit 28 in step S224, synchronization in thefrequency domain (frequency hopping pattern) and in the time domain(time slot) is established between the communication module 511 and thecommunication unit 28, thereby entering the state in which a data link(communication link) is established (state 1).

[0201] For example, when a data link is first established between thecommunication unit 28 and the communication module 511 by Bluetooth, instep S205, the communication module 511 sends a PIN (PersonalIdentification Number) code to the communication unit 28 so as toauthenticate each other. The PIN code sent from the communication module511 is received by the communication unit 28 in step S225, and then,various link keys are set between the communication module and thecommunication unit 28 based on the PIN code, random numbers, etc. ThePIN code may be encrypted before being sent and received by using apublic key provided for the communication module 511 by thecommunication unit 28. That is, in this case, the communication unit 28manages the private key associated with the public key provided for thecommunication module 511. Accordingly, the security can be enhanced,thereby making it possible to perform Bluetooth communication morereliably only between the personal computer 1 and the PDA 501.

[0202] The communication link established as described above iseffective only in a range of a few centimeters that can be reached byradio waves radiated from the communication module 511 in which theextremely low power mode is set. Accordingly, in step S206, thecommunication module 511 requests the communication unit 28 totemporarily disconnect the data link so as to switch the power mode sothat the communication module 511 can communicate with the communicationunit 28 even if it is away from the communication unit 28 at a certaindistance. In this case, the information obtained so far, that is, theBluetooth address, PIN code, etc., of the communication unit 28, isstored in the communication module 511.

[0203] Upon receiving this request in step S226, as in the communicationmodule 511, the communication unit 28 stores the information obtained sofar, i.e., the Bluetooth address, PIN code, etc., of the communicationmodule 511, and disconnects the data link (state 2).

[0204] In step S207, the communication module 511 sets the power modethat controls the output power to the normal power mode under thecontrol of the CPU 521 so as to reestablish a data link with thecommunication unit 28. Accordingly, Bluetooth radio waves from thecommunication module 511 can reach up to, for example, a range of a fewdozen of meters.

[0205] The communication module 511 then proceeds to step S208. In stepS208, the communication module 511 specifies the personal computer 1 asthe terminal of the communicating party based on the information storedimmediately before the data link is disconnected, and requests thecommunication unit 28 to connect to the communication module 511.

[0206] This request is received by the communication unit 28 in stepS227, and the settings are made in both the terminals so as to establishthe data link between the communication module 511 and the communicationunit 28. That is, in this state, Bluetooth communication can beperformed, for example, within a range of a few dozen of meters that canbe reached by radio waves radiated from the communication module 511 inwhich the normal power mode is set (state 3).

[0207] The communication system shown in FIG. 24 in which a closelyplaced terminal can be specified as the terminal of a communicatingparty is applied to the information processing system formed of thepersonal computer 1 and the cellular telephone 11 shown in FIG. 1. Then,in this information processing system, the image indicating the closelyplaced terminal can be displayed on the LCD 32 of the personal computer1 in accordance with the distance between the terminal of thecommunicating party and the personal computer 1. That is, the user isable to recognize the communication distance at which the terminals canbe connected, thereby making it possible to reliably performcommunication between the terminals.

[0208] A set of the above-described processes can be executed by usingsoftware. In this case, a corresponding software program is installedinto a computer built in dedicated hardware or a computer that canexecute various functions by installing various programs, for example, ageneral-purpose computer, via a network or a recording medium.

[0209] This recording medium may be formed of a package medium recordingthe program therein, which is distributed to the user for providing theprogram separately from the computer, as shown in FIG. 2, consisting ofthe magnetic disk 41 (including a floppy disk (registered)), the opticaldisc 42 (including a CD-ROM (Compact Disc-Read Only Memory) and a DVD(Digital Versatile Disc)), the magneto-optical disk 43 (including an MD(Mini-Disc (registered)), or the semiconductor memory 43. Alternatively,the recording medium may be formed of the ROM 22 recording the programtherein or a hard disk contained in the storage unit 26, which isprovided to the user while being built in the computer.

[0210] The steps forming the program recorded in the recording mediumencompass operations executed in chronological order described in thisspecification. The steps also encompass operations concurrently orindividually performed.

[0211] In this specification, the system represents the entire apparatusconsisting of a plurality of devices.

[0212] Industrial Applicability

[0213] As described above, according to the present invention,communication can be performed with an electronic device via radiowaves, and the display of an image corresponding to the electronicdevice is controlled based on the input level of the radio wavestransmitted from the electronic device, thereby making it possible torecognize the communication distance at which the information processingapparatus and the electronic device can be connected. Thus, informationcan be reliably exchanged between the information processing apparatusand the electronic device.

1-10 (Cancelled)
 11. An information processing apparatus comprising:communication means for communicating with an electronic device viaradio waves; obtaining means for obtaining identification informationconcerning the electronic device; and display control means forcontrolling, among a plurality of electronic devices, an image of theconfiguration of the electronic device specified from the identificationinformation obtained by the obtaining means to be displayed based on aninput level of the radio waves transmitted from the electronic devicelocated in a communication range of communication performed by thecommunication means.
 12. An information processing apparatus accordingto claim 11, wherein: the obtaining means obtains the identificationinformation concerning the electronic device by one of a communicationsystem in which information is sent and received by electromagneticwaves and a Bluetooth communication system in which a communicatingparty is specified by searching for devices in an extremely lower powermode; and the communication means communicates with the electronicdevice based on the identification information.
 13. An informationprocessing apparatus according to claim 1 1, wherein the display controlmeans controls the image to be displayed with a level of transparencycorresponding to the input level of the radio waves.
 14. An informationprocessing apparatus according to claim 11, wherein the display controlmeans controls the image to be displayed at a position corresponding tothe input level of the radio waves.
 15. An information processingapparatus according to claim 11, wherein the display control meanscontrols the image to be displayed with a size corresponding to theinput level of the radio waves.
 16. An information processing apparatusaccording to claim 11, wherein the display control means controls theimage to be displayed with a level of resolution corresponding to theinput level of the radio waves.
 17. An information processing apparatusaccording to claim 1 1, wherein the display control means controls theimage to be displayed with a level of saturation corresponding to theinput level of the radio waves.
 18. An information processing apparatusaccording to claim 1 1, wherein the display control means controls theimage to be displayed by performing mosaic processing on the image inaccordance with the input level of the radio waves.
 19. An informationprocessing method comprising: a communication processing step ofcommunicating with an electronic device via radio waves; an obtainingprocessing step of obtaining identification information concerning theelectronic device; and a display control processing step of controlling,among a plurality of electronic devices, an image of the configurationof the electronic device specified from the identification informationobtained by processing of the obtaining processing step to be displayedbased on an input level of the radio waves transmitted from theelectronic device located in a communication range of communicationperformed by processing of the communication processing step.
 20. Arecording medium in which a computer-readable program is recorded, thecomputer-readable program comprising: an obtaining processing step ofcommunicating with an electronic device via radio waves; an obtainingprocessing step of obtaining identification information concerning theelectronic device; and a display control processing step of controlling,among a plurality of electronic devices, an image of the configurationof the electronic device specified from the identification informationobtained by processing of the obtaining processing step to be displayedbased on an input level of the radio waves transmitted from theelectronic device located in a communication range of communicationperformed by processing of the communication processing step.